1. Field
The disclosed embodiments generally relate to systems that process signals received from multiple antennas. More specifically, the disclosed embodiments relate to a system that uses an integrated phase-shifting-and-combining circuit to process signals received from multiple antennas which, for example, can be used to implement a phased-array antenna system.
2. Related Art
In wireless communication systems, performance can be improved by using multiple antennas to directionally transmit and receive electromagnetic signals. For example, a phased-array antenna system comprised of multiple antenna elements and associated signal-processing circuitry can be used to directionally transmit and receive an electromagnetic beam. In such a phased-array antenna system, the direction of the beam can be steered by adjusting the phase shifting for signals associated with the constituent antenna elements. Two key components of a phased-array system, which determine its overall performance, are phase shifters and combiners. Unfortunately, when phase shifters and combiners are implemented using on silicon using CMOS technologies, they are often associated with high signal loss at RF and mm-wave frequencies, and occupy a significant amount of silicon area.
Hence, it is desirable to reduce this signal loss and required area, in particular to facilitate the use of phased-array antennas in compact, low-power systems, such as in mobile devices.